now for some effects,like bold ,or ittalic
add
tformat.bold=true
or
tformat.italic=true

at default they are false,so play around abit

want bigger text?
Use .size
Still in the format variable we would add something like
tformat.size=15

our code so far

createTextField("tex",1,50,50,200,50)
tex.text= "I am a text field"
tex.textColor=0xff0000
var tformat:TextFormat = new TextFormat()
tformat.font="Courier New"
tformat.bold=true
tformat.size=15
tex.setTextFormat(tformat)
now lets say we wanted to make it an iput text field,for a game maby,then you would do this